Comparison of new patients with Bence-Jones, IgG and IgA myeloma receivingsequential therapy: the need to regard these immunologic subtypes as separate disease entities with specific prognostic criteria

Of the 61 newly diagnosed patients with Bence-Jones (BJ) myeloma presenting to our centre between May 1986 and December 1997, 53 received sequential t herapy (ST) comprising infusional chemotherapy (IC) followed by high-dose t herapy and autotransplantation with interferon-alpha 2b maintenance. The ou tcome was compared with 153 IgG and 39 IgA similarly treated myeloma patien ts. Response to IC and high-dose was comparable between the three subtypes but a significantly higher proportion of patients with BJ myeloma failed to receive high-dose compared to IgG (P = 0.003) and IgA (P = 0.04) myeloma. Median overall survival (OS) of patients with BJ myeloma (2.8 years) and ev ent-free survival (EFS, 1.2 years) was significantly shorter than for patie nts with IgG myeloma (4.5 years, P = 0.03 and 2.1 years, P = 0.03, respecti vely). However, among those patients who achieved complete remission there was no difference in OS and EFS between IgG and BJ myeloma. In distinction to IgG myeloma where age and beta M-2 were significant, Cox analysis on pre sentation features identified performance status and urine total protein as having significant impact on OS. We conclude that achieving CR is an impor tant treatment aim in patients with BJ myeloma, conferring a similar outloo k on survival as in patients with the IgG subtype, and there is a need to c onsider different subtype-specific staging systems when evaluating the resu lts of published or ongoing therapeutic trials.